Grinding or polishing or glazing machine

ABSTRACT

Apparatus for grinding or polishing or glazing or otherwise finishing flat or contoured-in-one dimension surfaces of a work as the work is held on a work table reciprocated rectilinearly along a horizontal plane in front-rear and end-end directions with reference to a tool mechanism in the form of a driven rotatable grinding or polishing or glazing wheel having a peripheral face providing the grinding or polishing or glazing action, with cooperant means for reciprocating the work table in the forward and rearward directions and simultaneously therewith in the end to end directions, and other means for simultaneously driving the tool mechanism vertically to bring the tool into and remove the tool out of working position with respect to work.

United States Patent McLeod [541 GRINDING OR POLISHING OR GLAZING MACHINE [72] Inventor: John P. McLeod, 21 School St., Hatfield, Mass. 01038 221 Filed: March 18,1970

211 Appl.No.: 20,566

[52] US. Cl ..5l/93 [51] Int. Cl ..B24b 3/00, B24b 5/00 [58] Field of Search ..5l/93, 233, 122, 100, 39

[56] References Cited UNITED STATES PATENTS 270,294 l/l883 Feust ..5l/93 UX 1,717,385 6/1929 Jung ..5l/233 1,988,577 1/1935 Scrimgeour ..5 H39 2,050,087 8/1936 Koning ..5l/93 X 2,458,708 1/1949 Johnson et al. ..5l/93 X 2,486,108 10/1949 Brunel ..5l/93 2,803,095 8/1957 Monica ..5l/l00 1 1 Oct. 3, 1972 3,251,157 5/1966 Clark ..5l/l00 Primary Examiner-Othell M. Simpson Atto rneyl(enwood Ross and Chester E. Flavin ABSTRACT Apparatus for grinding or polishing or glazing or otherwise finishing flat or contoured-in-one dimension surfaces of a work as the work is held on a work table reciprocated rectilinearly along a horizontal plane in front-rear and end-end directions with reference to a tool mechanism in the form of a driven rotatable grinding or polishing or glazing wheel having a peripheral face providing the grinding or polishing or glazing action, with cooperant means for reciprocating the work table in the forward and rearward directions and simultaneously therewith in the end to end directions, and other means for simultaneously driving the tool mechanism vertically to bring the tool into and remove the tool out of working position with respect to work.

4 Claims, 5 Drawing Figures P'A'TE'N'TEDIJBI 3 m2 sum 1 or 3 INVENTOR. JOHN R MC LEOD BY f ATTORNEYS.

PATENTED BT 3 I972 4 3. 694,965

' SHEET 2 0F 3 FIG.3.

INVENTOR. JOHN P. MC LEOD ATTORNEYS.

GRINDING OR POLISHING OR GLAZING MACHINE SUMMARY OF THE INVENTION The invention relates to a surface finishing machine tool of the type in which a rotary tool has a peripheral face for performing a work operation upon a workpiece as a work table, upon which the workpiece is supported, is reciprocated alternately forwardly and rearwardly so as to move rectilinearly along an X axis and simultaneously reciprocated alternately from end to end so as to move rectilinearly and laterally along a Y axis, while also simultaneously the tool may be driven rectilinearly along a Z axis so as to raise or lower its longitudinal horizontal axis and thereby to change the relationship of the workpiece and tool, all to the end that the entire surface of the workpiece to be conditioned is exposed to the action of the tool according to a predetermined operating program.

In known prior art construction of this general type, numerous problems are encountered, particularly with respect to reversing a rapidly moving and frequently heavy table and workpiece and providing a precisely controlled amount of lateral cross-feed consistently throughout the entirety of a fore and aft reciprocating cycle.

Surface finishing machines have been heretofore known but none has been known to give such a wide operating work table area so as to allow the working of a single workpiece or a large plurality of workpieces in a single operation, due principally to the arrangement of a stack of coaxially aligned grinding or polishing or glazing or other tools on a single arbor extending from machine end to machine end.

In its general organization, the machine envisioned consists essentially of a horizontal rotatable arbor or spindle mounting such as a grinding wheel or a plurality thereof (or a polishing wheel or a plurality thereof, or a glazing wheel or a plurality thereof) disposed vertically above a work table assembly mounted and driven so as to be advanced and retracted in fore and aft rectilinear reciprocation and simultaneously to be reciprocated laterally from end to end of the machine, while additionally, the arbor and its mounted tool or tools may be raised or lowered vertically relative to the work table assembly by hydraulically operated cylinder means and, if desired, in cases or work having a contoured surface, according to a cam-controlled program.

In brief, the following salient features are envisioned:

l. hydraulic straight line actuation which eliminates rapidly wearing parts such as cams, gears, levers, worms and the like;

2. enclosed hydraulic circuits which serve to raise and lower the tool for loading and unloading, which circuits also serve to counterbalance the tool and permit same to float as it follows planar surface or irregular contours or geometries without variation of a desired contact pressure;

3. enclosed hydraulic circuits which are not vulnerable to abrasives and remain free of lost motion for the machine life;

4. hydraulic actuation which allows complete flexibility of speed and magnitude, with adjustments being permitted without machine stoppage;

5. rugged construction which allows a capability of withstanding far in excess of normal operating stresses;

6. horizontal design which permits the tool to be removed and replaced within a very few minutes, thus allowing rapid change-over of operations;

7. horizontal design which also permits waist high effortless loading so as to reduce operator fatigue; and

8. structural design which allows any dimension of machine for adaptation to any work length.

The invention is aimed at providing an efficient, simple, and rugged table feeding and cross-feeding mechanisms and a cooperant tool and driving mechanism therefor, together with control systems for controlling the speed and reversal rates of the table and of the tool with maximum precision and flexibility and with infinitely fine adjustment.

The machine has a capacity for performing all degrees of grinding, polishing or glazing, and a great multiplicity of operations can be performed therewith such as roughing, brushing, cleaning, wiping, buffing to matte or high colored surfaces or to mirror finishes, satin-finishing, mirror-finishing, delusterizing, de-rusting, waxing, sanding, or preparing surfaces for electroplating or chemical treating, to name but a few.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view, in side elevation, of the apparatus of the invention, showing the machine from the tending side thereof;

FIG. 2 is a view, in end elevation, of the right or tool driving end of the apparatus as viewed in FIG. 1;

FIG. 3 is a fragmentary view, in side elevation, showing the cam means of the invention;

FIG. 4 is a view, in top plan, of the work table as sembly; and

FIG. 5 is a view, partly in end elevation and partly in section, of the left end of the work table assembly as viewed in FIGS. 1 and 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT As best illustrated in FIG. 1, the basic machine comprehends a supporting base or frame 10 of a convenient height and of any conventional design and construction so as to support upwardly of a flooring and upon its upper planar surface 12 a horizontally movable main slide assembly, generally indicated by 20, having a capability of reciprocating alternately rearwardly from the tending side of the machine (seen in FIG. 1) to the opposite far side thereof and reversely in an opposite forwardly direction, which main slide assembly 20 in turn mounts thereupon in parallel relation therewith a work table assembly, generally indicated by 40, having a cross slide capability of reciprocating alternately endwise from the left end of the machine to the opposite right end thereof and reversely in an opposite endwise direction.

It is to be understood at the outset that the fore and aft rectilinear reciprocation of the main slide assembly and the sidewise rectilinear reciprocation of the work table assembly may be simultaneously performed or that one or the other such reciprocation may be selectively precluded according to the work load assigned to the machine and the specific result desired.

Reciprocation of main slide assembly 20, with respect to base 10, is upon a plurality of spaced, horizontally disposed base rails 22 stationarily secured to the base and extending in the front to rear machine direction perpendicular to the longitudinal axis of a tool, generally indicated by 70, disposed upwardly thereabove.

Ways 24, one mounted on the top of each base rail 22 so as to overhang or project outwardly of one side of its respective base rail, define a pair of horizontally disposed roller surfaces, upper and lower, along which roller surfaces strategically located rollers 26 mounted in provided insets in the respective slide rails 28 of the main slide assembly are rideable, the slide rails likewise extending in the front to rear machine direction, one adjacent each base rail. If desired additional rollers may be provided so as to rideon the outboard ends of the respective ways. In lieu of rollers, Teflon shoes or sleds could conceivably be used.

Ways 24 are so disposed with respect to base rails 22 as to elevate the main slide assembly upwardly of base wherefor it may readily reciprocate relative thereto.

A front end plate 29 and a rear end plate may be provided to enclose the respective ends of the main slide assembly.

The driving and reversing mechanism for actuating the main slide assembly in fore and aft travel comprises a conventional hydraulic operating cylinder 34, controlled by a reversing mechanism of usual design, and therefore not shown, and mounted on the base centrally thereof.

The reversing function may be served by a pair of limit or reversing switches strategically located on the base for limiting the stroke of the cylinder piston 35 and hence the extent of the travel of the assembly in each direction. That is, each limit switch is actuated from a first position to a second position by a respective lug which travels with the main slide assembly and contacts the respective reversing switch at the end of each stroke to thereby reverse the direction of piston travel and hence the travel of the assembly.

The reversing function may be otherwise served by means of a circuit of any conventional design and directly connected to the piston for driving the piston of the cylinder first in one direction and then in the opposite direction so that the main slide assembly is reciprocated forwardly and rearwardly alternatingly.

The magnitude of travel is adjustable and may be operated at extremely high frequencies.

The work table assembly is mounted on and upwardly of the main slide assembly whereby the independent rectilinear reciprocating operation thereof is achieved.

Such reciprocation is in the manner of a cross slide, being upon a pair of spaced, horizontally disposed work table rails 42 fixedly mounted upon a worktable base 44 stationarily secured to the main slide assembly and extending in directions parallel to the longitudinal axis of tool 70 and perpendicular to the axes of base rails 22 and slide rails 28. As seen in FIG. 5, work table rails 42 each mount, in overhanging manner on the upper planar surface thereof, a work table way 46 extending in a direction parallel to the respective work table rail.

The work table assembly includes an uppermost planar work table top plate 48 supported by a saddle 50 from which depend opposite front and rear strip or side walls 52 with a gib 54 extending from an inboard of the lower extremity of each strip or side wall and a dust plate 56 secured to the inboard end of each gib, with the inside surfaces of saddle 50 front and rear strips 52 and gibs 54 mounting strategically located anti-friction bearing sets 58. If preferred, anti-friction sleds or shoes, formed for example of Teflon, could be used in lieu of bearings.

As the work table assembly is driven, the bearings or shoes being in pressure-confined engagement with the upper and lower and outboard end surfaces of the ways, true horizontal movement thereof is allowed with an absence of any relative lateral motion so that the work table assembly is maintained in proper alignment and registry relative to the tool.

The mechanism for driving the work table assembly in two directional travel includes a hydraulic operating cylinder 60 mounted on the main slide assembly centrally thereof beneath work table 48 and controlled by such as limit switches strategically located on the main slide assembly for limiting the piston stroke and hence extent of the travel of the work table assembly in each direction. Here again, the reversing function may be otherwise attained as by means of a circuit of any conventional design and directly connected to the piston for driving the piston first in one and then in the opposite direction so that the work table assembly is reciprocated from machine end to machine end alternatingly.

Thus, it will be observed that the work table assembly is mounted for rectilinear motion parallel to the longitudinal tool axis and simultaneous with the transverse to the front to rear reciprocation of the main slide assembly.

The use of hydraulic cylinders and control mechanisms therefor for driving the assemblies is particularly advantageous in the ease and simplicity of speed control which they afford.

The feeding and cross feeding may be variably controlled independently of each other with infinitely fine incremental adjustments so that any desired stroke in both feeding and cross feeding directions may be realized and further so that abruptness is reversing is minimized.

As the main slide assembly is being so driven forwardly or rearwardly, the work table assembly 40 may be independently advanced and retracted laterally so that the strokes of one assembly are continuously along different paths with respect to the other, and, more importantly, to the work.

Contrariwise, switch means are provided wherefor the forward and rearward reciprocation of the main slide assembly may be selectively attained without the simultaneous crosswise reciprocation of the work table assembly, and vice versa.

Reciprocation along either axis can be locked out of action at the option of the operator.

Base or frame 10 additionally mounts, at each of its opposite ends, a tool supporting column, generally in dicated by 80, for the joumalling of an arbor or spindle 104 mounting therebetween and upwardly of and over the work table assembly.

Each tool supporting column comprises a base rail 82 fixedly mounted upon base 10 and from which extend upwardly thereof a pair of spaced vertically extending tool columns 84 interconnected at their upper extremities by a tool supporting column cross arm 86.

A strain bar 87 may be provided to interconnect between the opposite left hand and right hand tool supporting columns for obvious reasons.

Within the defined frame of the supporting tool column, a pair of spaced vertically extending jack shafts 88 are disposed with opposite terminals seated in provided seats in base rail 82 and cross arm 86 and allow for the vertical reciprocation of a jack spindle feed control comprised of a pair of jacks 90, each circumscribing and slidable along a shaft 88, the jacks of the pair being interconnected at their opposite ends by a lower jack cross arm 92 and an upper jack cross arm 94. If desired, the components of the jack spindle feed control can be made unitary.

Lower and upper jack cross arms 92 and 94 provide seating for a pair of spaced vertically extending or bar support shafts 100 upon which an arbor bearing housing 102 in which the end of arbor or spindle 104 is journalled.

Arbor 104 is driven by means of a pulley 106 keyed to one end thereof and having a belt 108 entrained therearound and likewise entrained around another pulley 1 l0 journalled with respect to base and driven by a motor 112 mounted within the base. The pulley may be variably tensioned by any conventional compensating means to assure uniform contact pressure throughout the working operation.

The tool is mounted on the spindle or arbor disposed between the left hand and right hand tool supporting columns and may be in the form of a roll 120.

As will be seen, the tool or roll is floating in the respect that it may be lowered toward the work manually or automatically so as to compensate for normal wear-down of the tool and/or for the wear-down of the workpiece through the grinding action and also that it be raised or lowered intermittently during operation as the tool follows the contour of the workpiece.

The tool may be composed of a plurality of standard grinding rolls mounted upon the arbor in a side by side relationship to give the effect of an elongated grinding roll.

Alternatively, polishing or glazing or other types of rolls can be mounted upon the arbor depending on the contemplated work assignment.

The tool may be controlled as to its elevation by means of the jack spindle feed control which may be raised or lowered by virtue of sliding the control vertically with respect to jack shafts 88 according first to the bringing to bear of the tool upon a flat workpiece or second to a cam action provided through a cam follower 130 which projects outwardly from the inboard side of lower jack cross arm 92 and rides upon an adjacent vertically disposed cam 132 fixed to a cam rail 134 mounted upon the main slide assembly and extending in a front to rear direction.

As the main slide assembly is driven in front to rear and rear to front directions, cam 132 moves therewith and cam follower 130 accordingly follows wherefor the jack spindle feed control is raised or lowered accordingly, the cam being selectively employed so as to follow the contour of the work piece.

Manual drive for raising and lowering the tool may be by means of a hand wheel (not shown) and can be effected even while the machine is operational. Hand wheel adjustment allows compensation for normal wear-down of the tool.

The tool contact pressure is hydraulically controlled by means now to be described.

On each side of the machine, a pair of hydraulically operated cylinders 140 and 142 are mounted on the respective tool supporting column above the jack spindle feed control and on base rail 82 below the jack spindle feed control, each cylinder being fixed to the jack spindle feed conuol for driving same in opposite vertical directions and accordingly therewith arbor bearing housing 102 and hence arbor 104 and its supported tool, all wherefore any predetermined uniform pressure of the tool upon the work may be brought to bear and maintained.

The cylinder operating function may be controlled by any circuit of conventional design such as independently adjustable directional flow valves which may individually or unisonly control the speed of raising and the speed of lowering the tool as well as the pressure exerted by the tool.

By varying the speeds and pressures, increased sensitivity of the floating action can be realized, same being especially desirable in the case of extremely difficult geometrics.

The arbor or spindle upon which the surface finishing medium is or are mounted is thus observed to be float mounted so as to control the work at any predetermined uniform pressure, which pressure is quickly adjustable in infinite increments.

By such design it is possible to wear the tool down in diameter and also to change the thickness of the workpiece without making a manual tool pressure or spindle adjustment.

Means may also be provided for feeding the tool incrementally vertically downwardly .with each successive pass of the machine.

The mechanism control circuits (not shown) can be incorporated into the operating control circuit by which the main feed slide and cross feed slide and arbor may be caused to traverse rapidly, such circuits providing in general for over-ridingly operating the respective pistons in either direction for such rapid traverse and for inactivating the feed mechanism during the interval.

Optional means may be provided so that in cases where the work has an unusually severe contour, the pressure may be automatically relieved as the tool climbs upwardly along the curvature and restore the pressure as the tool moves downwardly therealong maintaining a constant action throughout the dimension of the work.

The workpiece can be held on the upper planar surface of the work table assembly mechanically or magnetically, by vacuum or otherwise.

Electrical controls (not shown) include safety control circuits arranged to automatically arrest all machine motions simultaneously, to prevent entry of foreign matter, jammed work and the like and to provide a positive safety guard against physical hazards.

The apparatus will be observed to be readily accessible on both its tending and for sides so that a through feed feature is allowed if desirable.

Thereby the machine can be adapted for single passes with unloading at the rear of the machine as well as multiple passes.

In summary, the apparatus can be seen to serve for grinding or polishing or glazing or otherwise conditioning a flat surface of a workpiece, firstly, as the main slide assembly and work table assembly are driven forwardly and rearwardly, secondly, as the work table assembly is driven from end to end, or thirdly, as the work table is driven from end to end simultaneous with the driving of the main slide assembly forwardly and rearwardly, all relative to a rotating tool disposed above the workpiece carried by the work table assembly and driven downwardly theretoward for the work performing operation.

The apparatus can also be seen to serve for grinding or polishing or glazing or otherwise conditioning a contoured-in-one-dimension surface of a workpiece during the course of any one of the programs outlined in the next above paragraph while simultaneously therewith the tool is driven vertically toward and away from the workpiece according to the contoured surface of the workpiece.

Although the invention has been described in detail with reference to its preferred embodiments, it will be appreciated that numerous modifications will readily occur to men skilled in the art and that such may be made without departing from the scope of the invention.

lclaim:

1. In a machine tool for grinding or polishing or glazing a flat or contoured-in-one-dimension surface of a workpiece, the combination of:

a support structure,

a main slide assembly being altematingly reciprocatable in a horizontal plane between the forward and rearward sides of the support structure,

means for alternately reciprocating the main slide as sembly,

a workpiece supporting table assembly mounted on the main slide assembly and being alternatingly reciprocatable in a horizontal plane between the ends of the support structure,

means for altematingly reciprocating the table assembly,

means for holding the workpiece upon the table assembly,

tool supporting means at each opposite end of the support structure,

a tool rotatable mounted upon the tool supporting means on an axis transverse to the direction of movement of the main slide assembly and disposed in a horizontal plane above the plane of the table assembly and having a peripheral face movable into workpiece engaging position relative to the workpiece,

means for driving the tool, and cooperating cam means on the main slide assembly and the tool supporting means for vertically motivating the tool toward and away from the workpiece according to the contour of the surface thereof to be operated upon the tool.

2. In the machine tool as set forth in claim 1, the tool comprising a grinding roll.

3. In the machine tool as set forth in claim 1, the tool comprising a polishing roll.

4. In the machine tool as set forth in claim 1, the tool comprising a glazing roll. 

1. In a machine tool for grinding or polishing or glazing a flat or contoured-in-one-dimension surface of a workpiece, the combination of: a support structure, a main slide assembly being alternatingly reciprocatable in a horizontal plane between the forward and rearward sides of the support structure, means for alternately reciprocating the main slide assembly, a workpiece supporting table assembly mounted on the main slide assembly and being alternatingly reciprocatable in a horizontal plane between the ends of the support structure, means for alternatingly reciprocating the table assembly, means for holding the workpiece upon the table assembly, tool supporting means at each opposite end of the support structure, a tool rotatable mounted upon the tool supporting means on an axis transverse to the direction of movement of the main slide assembly and disposed in a horizontal plane above the plane of the table assembly and having a peripheral face movable into workpiece engaging position relative to the workpiece, means for driving the tool, and cooperating cam means on the main slide assembly and the tool supporting means for vertically motivating the tool toward and away from the workpiece according to the contour of the surface thereof to be operated upon the tool.
 2. In the machine tool as set forth in claim 1, the tool comprising a grinding roll.
 3. In the machine tool as set forth in claim 1, the tool comprising a polishing roll.
 4. In the machine tool as set forth in claim 1, the tool comprising a glazing roll. 